Dishwashers have a washing chamber including side walls, a top wall and a bottom wall, and a water circulation system mounted in the bottom wall of the washing chamber. The circulation system pumps water upwardly through a rotating wash arm for spraying water onto the dishes and other objects to be cleaned within the washing chamber. Typically, the water sprayed from the wash arm collects in the bottom of the washing chamber and is strained so as to remove large food particles from the water. The strained water is then recirculated by the circulation system for further spraying of the dishes.
A problem associated with conventional dishwasher circulation systems is that smaller food particles pass through the strainer, and thus through the circulation system. These smaller food particles recirculate in the circulation system and tend to become redeposited on the dishes and other articles being washed.